This is a proposal to continue studies of incessant activity in cities, and conclude a research program on this topic. A large body of information has been gathered, systematized, and put in accessible form. The predominant work in these two concluding years would be qualitative and quantitative data analyses for the following aims: 1) to produce a theoretical and partly empirical time-census for cities, including a classification of activities and estimates of the wakeful population involved; 2) to develop a conception of the city as a 24-hour system and the problems of such a system; 3) to infer future conditions, especially the prospects of reaching limits to expansion of wakeful activity and the role of energy supplies and shortages; 4) to interpret the implications of these trends for individual well-being from the viewpoints of shift workers, out-of-phase life styles, and experience of ordinary (daytime) city dwellers in an incessant milieu; 5) to generate a constructive policy for planning and coping with increasing wakefulness at all hours, using a key principle of enlightened scheduling both for individuals and for large social systems.